As the market expectation for the performance of electronic components remains focused on faster speeds and smaller sizes, designers continue to look for ways to increase electron flow between and within the components of electronic systems without increasing the size of those components. Electrically conductive materials such as copper, gold, aluminum, tin, and silver are characterized by high conductivity and low loss of electron flow. Such electrically conductive materials are thus often selected as the material for current-carrying structures such as interconnect structures within electronic components, interconnect structures between electronic components, and passive devices within electronic components. Examples of interconnect structures within an electronic component include single-level metal systems and multi-level metal systems. Examples of interconnect structures between electronic components include wire bonds, and examples of passive devices include inductors, resistors, and transformers.
Current-carrying structures are often operated at high frequencies of greater than approximately one gigahertz (GHz). At these high frequencies, however, the distribution of current or electron transmission through a current-carrying structure is compromised by a skin effect. The skin effect crowds the electrons toward an outside skin of the current-carrying structure and effectively decreases a cross-sectional current-carrying area of the current-carrying structure. The skin effect thus acts as a drag on energy efficiency and electron transmission in current-carrying structures.
Another problem for current-carrying structures such as wire bonds is that wire bonds have an inductive loss and an impedance. A high loss in a wire bond significantly affects the ability of the wire bond to carry a signal, particularly at high frequencies. Therefore, a wire bond with high loss greatly limits the distance across which the wire bond may be used as an interconnect structure between components. Furthermore, although multiple ground wire bonds may be added to an electronic component, the impedance of a wire bond with such multiple ground wire bonds is not easy to control.
The above-described skin effect and impedance problems may be reduced by increasing a surface area per unit of distance in current-carrying structures, thus increasing a current-carrying cross-section in such structures and planar controlled impedance configurations. As an example, a wider metal layer can be used to achieve this increase in current-carrying cross section, but at a significant cost of increased component size, particularly a larger footprint. Therefore, a need exists for an electronic component having a current-carrying structure with an increased current-carrying cross-section while a footprint of the electronic component does not increase in size.
For simplicity and clarity of illustration, the drawing figures illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the invention. Additionally, elements in the drawing figures are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of embodiments of the present invention. The same reference numerals in different figures denote the same elements.
The terms first, second, third, fourth, and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein.
The terms left, right, front, back, top, bottom, over, under, and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. The term coupled, as used herein, is defined as directly or indirectly connected in a mechanical or non-mechanical manner.